A 14 year old boy presented to the emergency department with a 10 day history of pain in his left hip. He reported that the pain had started after he kicked the ball during a soccer game. The pain was not particularly intense—he played until the end of the match—but it had persisted since then, tended to recede at rest, and reappeared during soccer training.

No swelling or bruising was seen on inspection of the inguinal area. He could walk and bear weight on his left leg without pain. Moderate tenderness was referred to the inguinal region, slightly below the inguinal ligament. Movements of flexion and lateral rotation of the hip were limited because of pain. A diagnosis of pelvic muscular strain was made and he was discharged with anti-inflammatory drugs and rest for one week. He was initially well but the pain recurred when he began to play soccer one week later. Plain radiography was then performed (fig 1⇓).

Questions

1. What does the radiograph show?

2. What is the diagnosis?

3. How does this condition usually present?

4. What are the treatment options?

5. What is the prognosis?

Answers

1. What does the radiograph show?

Answer

A bone fragment displaced from the pelvis.

Discussion

Plain radiography of the pelvis shows a 1 cm bony fragment displaced laterally to the pelvic bone (fig 2⇓). A subtle cortical irregularity of the pelvis is also visible, which suggests that the fragment originated from the anterior inferior iliac tuberosity.

A conventional anteroposterior radiograph is the imaging modality of choice when a pelvic fracture is suspected: displaced bone fragments are usually seen as radiopaque particles lying immediately adjacent to the parent bone. However, when the …